What sci-fi movie is this?

[fruitcake1]

I watched the start of this movie several years ago and now can't remember the name. It was not animated. It started where an astronaut dies when the shuttle he and two others are piloting back to earth burns up while reentering the earths atmosphere. He then wakes up in a bubble in a lake to see a hooded figure coming at him with a spear. He crawls out of a lake to find lots of other people in the same situation, and a pillar that dispenses capsules with food and clothes. He is then taken prisoner by men under the authority of a roman who has set himself up as the world leader. The astronaut keeps having dreams about going up river in something like a paddle boat. The hooded figure opens the cage where the astronaut and several others, including the last alien on earth, are being held. It seems they all died, then woke up in the lake, but nobody else had seen either the large bubbles or the hooded figure. I think there was also something about a crystal in the "throne" of the roman that they eventually needed to steal to do something with the boat. I know this movie sounds similar to Riverworld, but it isn't. I watched Riverworld yesterday and it's not the one I am looking for. If you know which movie this is please let me know. Thanks!